Process of fixing nitrogen and electric furnace for effecting the same.



J. E. BUCHER.

PROCESS OF FIXING mTRdEN AND ELECTRIC FURNACE'FOR EFFECTING THE SAME. APPLICATION FILED JUNE 25, I9I4.

1,174,667. Patented Mar. 7,1916.

2 SHEETSSIIEET I.

1-. E. BUCHER.

PROCESS OF FIXING NITROGEN AND ELECTRIC FURNAI J E FOR EFFECTING THE SAME. APPLICATION man JUNE 25.1914.

Patented Mar. 7,1916.

2 SHEETSSHEET 2- PRE-HE/I TER AUXILIARY PRE-HEA TER Y MAG/VES/A BR(0K/ K/ESELGl/HR WATER J2 C/(ET REVOLVING TABL UNITED STATES PATENT OFFICE.

JOHN E. BUCHER, OF COVENTRY, RHODE ISLAND, ASSIG-N'OR '1 O NITROGEN PRODUCTS COMPANY, OF PROVIDENCE, RHODE ISLAND, A CORPORATION OF RHODE ISLAND.

PROCESS OF FIXING NITROGEN AND ELECTRIC FURNACE FOR EFFECTING THE SAME.

Specification of Letters-Patent.

Patented Mar. 7, 1916.

Application flled June 25, 1914. Serial No. 847,337.

To all whom it may concern:

Be it known that I, JOHN, E. BUoHER, -a

citizen of the United States, residing at Coventry, in the county of Kent and State of Rhode Island, have invented certain new and useful Improvements in Processes of Fixing Nitrogen and Electric Furnaces for Efi'ecting the Same, of which the following is a specification. I

This invention relates to a process and means for the fixation of atmospheric nitrogen; the free nitrogen being caused to combine with'carbon and with a suitable base forming element such as an alkali or alkaline earth metal, to form a cyanogen com--- pound.

This combination is effected through the intermediacy of a suitable catalyzer which is capableofrendering the carbon reactive, and the cyanogen-compound-forming reaction is in the hereindescribed process effected in a suitable receptacle or furnace, heated'either directly, or in part at least directly, by passing electric current through the mass of material which supplies preferably all of'the constituents of the cyanogen compound to be formed other than the nitrogen.

The preferred process is especially char acterized by the fact that the electrical heating is employed in such a manner that the charge itself acts, either entirely, or in art,

- as the electrical resistor.

A charge of the preferred material, or rather mixture of materials, conducts heat rather slowly and, if it be attempted to heat the mass thereof exteriorly, heat has to penetrate. the interior portions by being conducted through the walls of the retort and the outer layers of the charge.

Owing to the extremely efficient mixture and the rapidity with which the nitrogen may be supplied, especially to briqueted materials' of the character in question, the rapidity of the process is very seriously reta'rded by this relatively slow heat penetration; and it has been one of the principal objectsof the present invention to surmount i, furnaces must be so designed that the heat has to penetrate but a comparatively short distance into the charge and even then the temperature outside has to be kept much higher than that necessary for economical cyanid formation, to the end that a reasonably rapid heat penetration may be assured. This involves the additional serious disadvantages that the retorts, if of iron as they preferably are, soon becomes highly carburized and are more likely to melt or become injured by oxidation; that the exterior portions of the charge may be heated so as to melt or sinter the catalyzer, which is preferably pulverulcnt, at least initially; and that in the hotter exterior portions there may occur such a volatilization of the al-' kali compounds or their equivalents as to completely disintegrate the briquets with' consequent tendency to flood other portions -of the charge with such an excess of alkali material as to make such portions partially or entirely inactive. I have found that these disadvantages, which are practically inherent in'substantially all methods of external heating can be overcome completely by'internal electrical heating. through the use of the charge itself as a resistor.

' Nitrogen fixation, by the use of an elec-- trical' resistor made up of such materials as a mixture of finely divided iron, carbon and sodium carbonate has not heretofore been accomplished, and its accomplishment presented some apparently serious diificultles.

For example, while such a resistor is, largely by reason of the presence of the solid alkali carbonate, virtually an insulator, I have found that its resistivity may be so enormously diminished upon heating, as to con- 5 vert it to a fairly good conductor which be-, comes plastic 'while'at the same time ingrehere stated that iron and carbon, both finely divided, may be mixed with, for example, alkali carbonate and briqueted under pressure after the addition of suitable quanticurrent can flow to all ties of water; or, the mixture may be heated slightly above the meltingpoint of the al-- vkali carbonate while substantially excluding air, and briquetedunder suitable pressure. In the latter case the briquets are already at the temperature of the cyanid formationand this preheating is'of great advantage.

If the briquets are prepared moist, they are best driedquickly so that theymay'befirm and'even this slight heating is of great advantage, not only because of the heat thus supplied to the briquets, but also on account to this preheating.

of the increase in electrical conductivity due The briquets may be made in many shapes.

but the ones preferably used in this process were pressed through adie and were made cylindrical'in shape, being each one quarter of an inch in diameter and about one inch long. A resistor of such briquets presents large interstices through which the nitrogen ortions of the resistor, after which it quickly penetrates by difl'usion through the very small interstices or pores between the particles of iron and carbon.

The briquets are in general only in contact with each other at points and hence at first offer very poor electrical contact; and

the same must be true to some extent of the very-small irregular fragments'of iron and carbon of which the briquets are formed,

' .which are, in addition, more or less separated by the powdered sodium' carbonate; thelatter being an insulator when cold.

5 The entire resistoris hence almost anonconductor' when cold and ,even 500 volts E; M. F. may send but a very slight current through.

a five-foot column in a one-inch tube. 3

The very slight current soon reaches a maximum when the heat lossby: radiation counterbalances the'heating effect of the [allowed to actuntil it flowsfreely. This until the resistor is of the desired len current and it would hence require anexcessively high. voltage to bring the heat-- ing action to the critical point and a still more impractical voltage to do-this expeditiously. Increasing the pressure on the mass increases the conductivity somewhat but notto the desired extent. -.This initial resistance can be overcome by using a shorter column which permits of theuse of a more reasonable voltage and when the current flows freely, the electrodes may be' partly withdrawn and more briquets added after which the current maybe again procedure may be repeated easily and quickly in a furnace of the character shown in Figure 1 of the accompanying drawigntgls Theycurrent is then allowed to flow until the entire mass shows a uniformly bright incandescence and the conductivity of the resistor has incrcasedover a thousandfold,

equalize heat production.

in some cases. It is also possible to. avoid the use of currents of high voltage by preheating the briquets or using them hot as t ey come from. the drier in which .their moisture is removed. When a mass of briquets is used as a resistor, the conductivity of the carbon and soda ash increases while that of the iron decreases, and, as the temperature rises heat is developed at the points of poorer contact, but asthe temperature continues to rise the briquets soften at first at such points and the weight of the column then presses them together so as to produce a surface contact with comparatlvely good conductivity whereupon excessive heating .at such surfaces ceases automatically and other. portions in turn, become heated; thus equalizing the heating of the resistor, Also if the resistor is of such a' shape that the current may flow in channels, producing excessive heating, this may be equalized by' reducing the voltage of the current or shutting it ofl entirely until the heat has been conducted away to. the cooler parts; thus again equalizing the resistance and consequently the heating.

- Injurious local heating in such a resistor is further counteracted by the latent heat of fusion of the alkali carbonate which is present, and even more" eifectively 'by the very rapid volatilization of such alkali compounds, where the temperature temporarilygets tooclose to'the melting point of the.

carburized iron. Theicondensationof this volatilized matter .on the neighboring colder parts heats such neighboring parts; and thereby again tends to equalize heatthroughout. the mass. The gas current through the coarse interstices'of the resistor greatly increases .this favorable heat distributing action both by convection and increasing volatility. ,The heat changes due to vaporization and condensation not only actdirectly as a safety device to secure uni- 7 form heat distribution in the resistor, but, also effectively, by thus controlling the heat generation itself, effect a consequentialauthus causing rapid heat absorption with simultaneous read uStment, of resistance to The enormouschange, of conductivity with temperature makes such a resistor an excellent thermostat for'the process, as is only necessary-to determine forgiven conditions what amperage is necessary and 'theninsert the proper fuses, c1rcu1t breakers and transformers into the circuit. Thus the current may be safely and automatically controlled even when heat is generated very rapidlyin the charge. A 100 ampere current at I 104 volts can readily be passed through acylindrical column of briquets 1% inches in diameter by 10 inches in length, which current will supply enough heat to complete the above reaction in about thirty seconds. On a small scale with properly prepared briquets I have actually converted the carbonate into c'yanid in less than one minute. Such a very rapid generation ofelectrical energy in the resistor allows comparatively little time for loss by radiation and hence gives very high heating efiiciency.

;,f-This resistor contains an extremely active supports.

catalytic solution surface which renders the carbon more active thereat by presenting it While in solution in, for example, iron, to the elements which are to react therewith.

It alsoprovide's for very free access of nitrogen to the reacting surface, and permits rapid heating of the interior portions of the charge. The preferred resistor, further, permits of very free circulation of alkali metals or compounds through its interstices by reason of its porosity, and of the absence therefrom o f-injurious binders and Because of these and other advantages it permits cyanid formation more rapidly and efficiently than has heretofore been possible.

v The resistor maybe made inmany different'forms. ,For example, it may bepressedthrough adie in one piece, with suitable perforationsto' conduct the gases therethrough.

' The --iron-carbon-sodium carbonate mixture may even be usedin the powdered form without briqueting; but in any case the resistor should be so prepared andv used as to rovide and maintain an enormous cata- 1 tie solution surface at which the cyanidorming reaction ma' takeplace, while at the sametime provi ing for free access of alkali metal-or compounds thereof or equiva lents'jof such metal or compounds, together Ywith .nitrogen, thereto. v

In the' accompanying drawin form a art-hereofI ave exempli .ferred urnace;- butas I'a-m aware of very s I which many changes and modifications which may V -be made herein without departing from the spirit of my invention and while yet .af- .fording 'means suitable for, the eifectuation ofthe herein described process, I 'desire in no way to be restricted to the form ofappa-j ratus shown nor indeed. to the specifically described steps of my process other than as set forth in the claims appendedhereto.

. Referring to the drawings: Fig.1 is a vered a pretical median section of a furnace in which my process may be carried out. Fig. 2 is a.

a section through said furnace taken on line IIII of Fig. 1.. Fig. 3 is a diagrammatic representation of a group of furnaces. Fig.

4 1s a somewhat'diagrammatic section of a modified construction adapted for continuous operation of the process. Fig. 5 is a section taken on line VV of Fig. 4, and Fig. 6 is a section taken on line VI-VI of said figure.

In the apparatusshown in Fig. 1 the fur- I nace comprises inner and outer cylindrical portions respectively designated 1 and 2. The inner one may be built of superposed magnesia brick and the space 3' therebetween.

may be filled with kieselguhr, or even ashes or some like refractory material. These tel- -escoped chimney-like sectionsmay be sustact with the resistor at different places to counteract the tendency of the current to flow in channels when the length ofthe resistor is too short as compared with its cross-section. This method of working and applying the. electrodes also insures positive contact and suitable pressure on the resistor,

under all conditions, thus preventing the formation ofarcs.

The base 4 has pivotally mounted therein able means 8 for rotating these bars to permit of-a discharge of the whole or of a portion of the. material within the furnace, into the chamber provided below said bars in the' base 4. This chamber may have anair-tight .closure 9 at an opening therein through which the treated and cooled .material deos'ited in said chamber, may be removed. he base 4 is insulatedly mounted, as at 10,

' a series of grate-bars 7 provided with suitand the operating parts .of the grate are 7 preferably provided with an insulatedor insulating handle 11. Nitrogen may be introduced through a pipe 12 which leads into the chamber below the grate, and said pipe may beinsulated from the base, as at 13, in

any suitable manner, and is further preferably provided with a valve 14 for regulating the inflow of nitrogen. The gaseous products of the reaction effected in .this furnace, which are principally. carbon monoxid, pass off ifromthe' upper portion of the furnace through a pipe 15,'which may be of magnesia brick or other suitable material; and the briqueted charge 16, which in the preferred construction,constitutes the resistor for the furnace, may be introduced through a hopper or chute 17, The latter has an' airtight cover or closure '18, and is also preferably provided with a slide or' gate 19, so that when gate 19 is closed a determined quantity' of briquets can be introduced into the.

space or chamber 20 between gates 18 and 19; cover 18 being thereupon closed .and the gate 19 raised to permit of this charge sliding down into the interior of the furnace.

In the present instance in the furnace shown,there are provided five electrodes .21,

of iron or other suitable material, which are insulateoly suspended by wire ropes 22 and pass downwardly through apertures in the cover 6, so that their lower extremities rest Y upon the upper surface of the' briqueted charge. The apertures in said cover through which these electrodes extend may be sealed by means of asbestos 23, or in any other suitable manner, a cap 24 being provided to retain the asbestos against upward displacement when the electrodes are elevated. Electrical connections are made to these electrodes either directly, or, through the cover 6 which engages said electrodes, and a lead 25 from a suitable source of current is connected to the'frame 25 of the cover 6. In the present case the five electrodes 21 are of course inlparallel. Assuming that the lead 25 is positive, current passes down through the electrodes and'enters the resistor mass 16 at the top thereof, traverses the same downwardly and passes out through the grate-bars 7, base 4 and returns to negative lead 26.

As above intimated, unless the briquet charge or resistor be preheated, its resistivityheats up and as its temperature rises its conductivity is enormously increased, permitf ting additional briqueted matter to be introduced through the hopper 20 from time to time." Th electrodes are then successlvely raised, wit or without rotation, by turning the cover throu h a suitable angle, and

allowed to drop ack into contact with the u per surface of the resistor, until a charge of sufficient de th has been introduced into the furnace, a er which the nitrogen current is turned. on and flows up through the inter ices between the bars 7 and between the br quets, effecting the cyanid-forming'reaction "according to the previously given equation.

Of course the nitrogen may be turned in, ifv desired, even when-the column of briquets short or shallow and with sub- Thoreupon current is allowed to a flow through the resistor which gradually fold or more.

stantially e ually good results. In practice the current 1s allowed to become of sufficient density to heat the resistor to from about 800 up to 1000 0.; although the cyanid forming reaction may take place at a materially lower temperature if suitable provi sion be made for effecting adequate 'volatilization, or in some cases liquefaction, of the alkahcompound or ts equivalent whleh constitutes the source of the metal which is to become the base of the cyanogen compound made as low as CS, or thereabout. Howi ever, on account 0 the cheapness of the alkaline compounds,-above specified, I'prefer to use sodium carbonate alone, or in certain cases to use a mixture of sodium carbonate and potassium carbonate. If the temperature of the operation be sufliciently high the cyanid formed Will be vaporized and will pass off together with'the carbon monoxid through the tube 15, to condense as soon as the rapidly lowering temperature permits, The cyanid formed may thus be separated from the resistor by electrical heating either with or Without the passage of a gas current alongkwith the cyanid vapor, or, it may even be distilled under diminished pressure. This use of the resistor for distilling cyanid from the reaction mixture, therein, materially aids in avoiding the great difiicultyof supplying heat from the outside of the retort to the interior of the poorly conducting charge.

As the charge settles fresh briquets may be introduced from time to time through the hopper 20 and when the mass has been sufli-' ciently treated,'the-cu1 rent is turned off and the briquets are allowed to cool and harden, after which the'grate bars are rotated and the now no longer plastic briquets'will hence drop through readlly. a

. By reason of the peculiar properties of the resistor above referred to' the electric heating of the mass maybe made economi- 'cally effective and far more uniform throughout than is possible when a similar mass of is formed, is' one of the most striking features of the present process and in certain I cases the difference in resistance between the briqueted charge when cold and the 'same charge when heated, let-us say, to.

about 1000 O. may even reach a thousand- This permits of the use of a current of such -low voltagethat an ordinaryilighting circuit may be used. Indeed itis possible by properly preheatingthe mass to employ a current of 50 volts or even lower E. M. F. It will be found advantageous in many cases, and particularly in this latter, to also preheat the nitrogen which is supplied to the furnace.

The electrical heating of the above described resistor which contains metal (resisti'vity 12) carbon (resistivity 1200 or more) and soda ash which is practically a fusible insulator, was at, first considered impossible of practical accomplishment; but I have proven that it can be done very efficiently when the above described measures are observed. In the carrying out of my present process there is involved, therefore, a movable chemical resistor, which is in large measure automatically self-regulating by enormous change in conductivity byvolatilization of one of its constituents, by internal endothermic chemical change, and by fusion of its internal insulator (soda ash, etc); this fusion of the soda ash, or

the equivalent thereof, producing a tremendous change in contact conditions be; tween the metallic and carbon portions of the mass, as well as relatively great electrical conductivity as compared with the conductivity of the comparatively cold, and, hence, also a correspondingly great increase in heat conductivity at high temperatures.

I believe that is hard to. over-estimate the value of these changes which so intimatelyconc'ern the heat regulation of the reacting mass and which in effect, and in combination with suitable fuses and circuit breakers, constitute a means for practically limiting the rise in temperature at any one point in the mass beyond that-temperature at.

whichit is undesirable to conduct the process. In this connection it may be noted that when a catalyzer such as iron is used in the asolid phase, it is preferably very finely divided and the eutectic point of the carbon saturated catalyzer should, in such cases, never be exceeded since the'catalytic solution surface would be thereupon ser ously impaired by fusion or sintering of the iron particles, which would result in a material decrease in the extent of'the catalytic surface and a consequent decrease in the effectiveness of the chemical resistor at such points therein as ,might be subject to such excessive temperatures. The catalyzer used is preferably iron or a carbon dissolving metal;.but it may also form nitrids to aid in the process.

' I may here point out that is highly desira-ble l in preparing the briquets, that'the catalyzer be most intimately associated with the carbon, and that duringthe cyanidforming operation the current of nitrogen. be directed into contact with the catalytic mafe'rial whileithe--base-forniing element, 1 or source of the same, 6. g. sodiumcar resistor when B and G as well as .to condense bonate, is also in contact therewith, whether' said element or compound be in the gase-' ous phase or otherwise.

Free oxygen should be carefully excluded from the reaction zone in the furnace and indeed from contact with the cyanid, after formation of the latter, so long as said cyanid. or equivalent cyanogen compound is hot. Obviously also the escape of cyanogencompound fumes should' be prevented, these latterbeing poisonous; while any" material waste of such material or of the volatilized sodium carbonate is costly. It should here be noted also that the columnar disposition of various other electrlcal heatingarrangements which may be made reasonably efi'ec tivefor the effectuation of my process. I

prefer that shown, howeve-r,-on account ofits simplicity and economy.

A series of furnaces of the type shown in Fig. 1 may be arranged as diagrammatically indicated in Fig.- 3, so that a hot charge in furnace A, for example, which has been treated to form cyanid therein, may bein furnace A before delivering it through pipes covered with .kieselguhr or the like to furnace B or. C; suitable valves being provided to permit of any desired disposi tion of the gaseousv current; Thus the treated briquets may be rapidly cooled preparatory to dropping .them out of the regas main 27 up; through the treated charge cooled by, passing cold nitrogen from the a action zone ofthe furnace while at the same time the nitrogen to be delivered to some {other furnace in the series ishighly preheated and heat is conserved. This also' I serves ,topreheat the briquets inlfurna'ces the poisono'us alkali and cyanid fumes. It, further,-

.permits the maintenance of a heat zone in the resistor at such temperatures that a 4 deposit of carbon. may occur therein under the influence of the catalyzer according to .--,the equation: 7

a 2co:co,+'c+ss,96o calories. In so far 'asfthis takes place,- it produces ashless carbon together with the simulta-ne-- ous internal heatingin the resistor'itself, and saves both carbon and grinding of the same.

In Fig. 4.1- have diagrammatically representeda furnace which may be continuously operated. Herein, a briquet resistor column 16' is fed more or less continuously through a preferably flattened channel 28, portions of which, not between electrodes,

may be of wrought iron pipe or the like which further may flare for a portion of the length thereof, as at 29. The channelwalls between the electrodes may'be of magnesia brick or some like non-conductive material. I prefer to water-cool theflared part 29 so as to quickly reduce the plasticity of the descending briquets before the latter reach the revolving table 30 or equivalent charge shifting or conveying device. A screw conveyer 31 or the like may deliver the charge in a continous stream, if desired, from a suitable hopper or receptacle 32', and the briquets before entering the reaction zone may be preheated as by burninglthe carbon monoxid, formed during the course of the reaction, in the pro-heater 7 indicated. The ascending gaseous reaction products'help to internally reheat the moving resistor and may emerge rom the furnace at 33. Electrodes 34, connected to bus bars 35, are suitably disposed around the channel 28' to establish the location of the reaction zone therein; said electrodes being preferably annuli of iron or other conductive material; and in the present case the electric current flows down through the chemical resistor from the upper to the lower of these electrodes. Around the pipe28 at the reaction zone and r'espectively above and below the electrodes, are

rings or blocks of magnesia brick, and a.

layer of kieselguhr is suitably retained around the outside of these rings-and around i the electrodes to insulate the furnace as far v ployed-in very large measure obviates the necessity for so doing and usually permits of a practically continuous operation of the furnace. Also, when external preheating is used,1it is desirable to heat the briquets in suchfa manner that the hotter briquets become mixed with the cooler ones toget an average uniform heat distribution in the re-' 'slstor; This may be done in a rotary fur.-

nace, or even by having a pre-heater at 36 around thehorizont al pipe through which theicbriquets are conveyed to the furnace, or.

I in other suitable manner.

If the part of the furnace between a and b 'is not filled with briquets, this empty space aware that, for example,.by

will serve as a mixing chamber as the briquets fall to the bottom. In this way, the initial formation of a comparatively good conductin annularlayer of briquets on the outside o the resistor, with a subsequent tendency to conduct too large apart of the current (thus leaving a comparatively cold core on the inside), may be avoided in continuously acting furnaces.

flow into proper contact with the electrodes and gaps across which arcing might occur are thus obviated.

If the furnace is to be operated with gases such as those containing nitrogen mixed with carbon monoxid, they are introduced, preferably highly preheated, into the reaction zone in the hotresistor at 37. By thus causing a more or less continuous advance of the resistor column through the heat or re action zone, to the already mentioned advantages of the stationary resistor, we add those of returning the upwardly escaping volatilized (but subsequently condensed) alkali metal and compounds to the heat zone of the moving resistor, to thus produce circulation without flooding the colderportions with alkali compounds, while at the same time introducing extra heat and ash-free carbon from without according to the equation (2) and avoiding the destructive action, on the cooling cyanid containing mass, of the CO produced coincidentally with the deposiis very desirable unless some such provision as that of the movable electrodes shown in the first described constructionbe resorted to; and whether the furnace be of the-continuous or discontinuous type ash free carbon may, if desired, be deposited from carbon monoxid in the preheating zone.

.In the appended claims the term cyanogen compound is to be regarded as of sufficient breadth tocover not only cyanid but other cyanogen containin substances, such, for example, as cyanami etc.; since I am roviding insuflicient carbon for the cyanid forming re" action, cyanamid will be formed.

Feinally, in'this application I desire to dicase, Ser. No. 864,690, filed Oct. 2, 1-914.

Having thus described my invention what I claim is: I l 1. Means for fixing nitrogen comprising rect attention to the division of the present 4 an electrically heated furnace having there- 'in a resistor which includes a catalyzer of low resistivity, carbon and material capable of supplying the base of a stable cyanogen compound to be be formed in said resistor, said resistor being adapted to permit of the passage I of nitrogen therethrough inflcontact with said catalyzer, and said'catalyzer holding a portionat least of said carbon in solution therein.

an electrically heated furnace having therein a resistor which includes a catalyzer of low resistivity, carbon and material capable of supplying. the base of a stable cyanogen compound to be formed in said resistor, said resistor being adapted to permit of the passage of nitrogen therethrough in contact with said catalyzer, and said'base supplying material having, when in the solid phase and at temperatures materially below those at whichsaid cyanogen compound may be formed, a high resistivity as compared" with that of said catalyzer, the resistivity of said resistor bein variable through wide limits by achange 1n phase'of said base'supplying material.

4. An electric furnace for fixing nitrogen which comprises a resistor which itself includes material capable of catalytically participating in a cyanogen-compound-forming reaction during the course of which reaction free nitrogen is combined with carbon and with an element capable of acting as the base of said cyanogen compound, said fur-- nace further comprising means for directing said free nitrogen into contact with said catalytic material while, said base forming element and carbon are also in contact therewith, electrical connections for passing current through said resistor to heat the same, and means to conduct away from the reaction zone in said furnace gaseous products of said reaction; a

'5. An electric furnace for fixing nitrogen which comprises a resistor which itself includes' carbon and material capable of. catalytically participating in: a cyanogencompound-forming reaction during the course of which reaction free nitrogen is combined with said carbon and with an element capable of acting as the base of said cyanogen compound, said furnace further omprising means for directing qid i g n into contact with said catalyticina 'terial while said base formin element and carbon are also in contact t erewith, and electrical connections 'for passing current through said resistor to heat the same.

6. An electric apparatus for fixing nitrogen which comprises an intersticed resistor which itself includes a .compound of a metal which is capable of acting as the base of a cyanogen compound carbon, and material capable of catalytically participating in a reaction efi'ected within the interstices of said resistor to form said cyanogen compound by combining the carbon present in said resistor with said metal and free nitrogen through the instrumentality "of-said catalytic material, said apparatusincluding electrical connections forpassingscurrent throughsaid resistor, and provisions for directing said free nitrogen into the interstices of said resistor. v

7. The combination of a resistor comprising a mass of briquets -in-which are pres-v ent in intimateassociation, a carbon containing cat'alyzer presenting an extended solution surface, and a compound'of a metal capable of acting as the base of a stable I cyanogen compound to be formed in said briqueted mass, said mass being porous to permit of the flow of a current of free nitrogen over and in contact with said solution surface, means for introducing said nitrogen current into said-ma'ss'and means for passing electric current in part at least through said resistor to internally heat the same.

8. The combination of a resistor comprising a mass of briquets in which are pres- 'ent in intimate association, a carbon con- ,taining catalyzer presenting an extended solution-surface, and a compound of a metal capable of acting as the base of a stable cyanogen compound to be formed in said briqueted mass, said mass being porous to permit of the flow of a current of free nitrogen over and in contact with said solution surface, means for introducing said nitrogen current into said mass and means for passing electric current in part at least through said resistor to internally heat the same, said catalyzer being solid and finely divided and said compound of said metal being initially in the solid phase but being subject to a change in phase as the temperature of the resistor is raised, whereby the resistivity" of said resistor is greatly lessened as the cyanidforming temperature is appiroximated. a

The combination ofa resistor comprlsing a mass of briquets in which are present,

in intimate association, finelyv divided carbon, finely divided catalytic material, and a compound of an alkali metal capable of *acting as thebase of a stable cyanogen compound'to be formed in said briqueted mass,

said mass beingporous to permit of the flow of a current of free nitrogen over and in contact with the extended surface of said catalytic material, means for introducing said nitrogen current into said mass, and means for passing electric current in part at least through said resistor to internally heat the same.

10. The combination of a resistor comprising. a mass of briquets in which are present, in intimate association, finely di-' vided carbon, finely divided catalytic material, and an oxygen containing compound ofanalkali metal capable of acting as the base of a stablecyanogen compound to be formed in said briqueted mass, said -mass being porous to permit of the flow of a current of free nitrogen over and in contact with theextended surface of said catalytic material, means for introducing said nitrogen current into said mass, and means for passing electric current in part at least through said resistor to internally heat the same.

11. The combination of a resistor comprising a mass of 'briquets in which are present, in intimate association, finely divided carbon, finely divided catalytic materiahand a carbonate of an alkali metal capable of acting as the base of a stable cyanogen compound to be formed in said briqueted mass, said mass being porous to permit of the flow of a current of free tended surface of said catalytic material, means for introduclng sald nitrogen current i nitrogen over and in contact with the excomprises briqueting a mass comprising a compound of a metal capable of acting as the base of a stable cyanogen compound carbon and a catalyzercapable of rendering said carbon reactive to combine with said metal and with free nitrogen to form said cyanogen compound, using the briqueted mass as a resistor in an electriccircuit to heat said mass to a temperature at which the cyanogen-compounddforming reaction may take place, (and passingfree nitrogen through the bri'q-ueted mass at said temperature to effect said reaction.

14. The .process of fixing. nitrogen which comprises preparing a mass" comprising a compound of anelement capable of acting -as the base of a cyanogen compound, carbon and a catalyzer intimately associated with' said carbon and capable of rendering-1t reactive to combine. with said element and said cyanogen compound. 1

with free" nitrogen to form said cyanogen compound, subjecting said mass to The action of an electric current, and passing free nitrogen through said mass. to formsaid cyano en compound.

15. comprises preparing a mass comprising a compound of-an element capable of acting he process of fixing nitrogen .which' as .the base of a cyanogen compound, carbon and a catalyzer intimately associated with said carbon and capable of rendering it' reactive to combine with said element and with free nitrogen to form said cyanogen compound, subjecting said mass to the direct actionot a dense electric current, and passing free nitrogen through said mass to form 16. The process of fixing comprises preparing a -mass comprising a compound of an element capable of acting as theibase of a cyanogen compound, carbon and a catalyzer intimately'associated with said carbonand capable of rendering it reactive to combinewith'said element and with free nitrogen to form said'cyanogen compound, preheating said mass preparatory to nitrogen which the passage therethrough of a dense-electric,

current, subjecting said mass to the action of said electric current, and passing free nitrogen through saidmass to form. said cyanogen compound. 17. The process of fixing nitrogen which comprises preheating a porous briqueted mass comprising a compound of an elementcapable of acting as the base of a cyanogen compound, carbon'and a catalyzer intimately associated with said carbon and capable of rendering it reactive to combine with said element and with free nitrogen'to' form said cyanogen compound, subjecting said mass tothe action of an electric current, and passin .free nitrogen through said mass to form sai cyanogen compound' '18. The process of comprises preheating a porous briqueted nitrogen which, I

masscomprising a compound of an element capable of actingas the base of a cyanogen compound, carbon and-a catalyzer intimately associated with said carbon and capable of rendering it reactive to combine with said" element and with free nitrogen to form said cyanogen compound, preheating said I mass preparatory to the passage there'- through of-a dense electric current, subjecting said mass .to the action of said electric current, and passing free nitrogen through said mass to form said. cyanogen compound;

' 19. The process of fixing nitrogen which comprises preparing a mass comprising a compound of an alkali metal capable of acting as the base of afstable'cyano'gen compound,-- carbon and a catalyzer intimately associated withsaid carbon and capable of rendering it reactive to combine with said element and with free nitrogen to form said and subjecting said mass to the action of an electric current and to free nitrogen and cyanogen compound, subjecting said mass to the action of an electric current, and passing free nitrogen through said mass to form said cyanogen compound.

20. The process of fixing nitrogen which includes preparing a mass comprising carbon intimately associated with an element of the iron group which is capable of dissolving carbon and of thereby rendering said carbon reactive to combine with free nitrogen and a metallic base to form a cyanogen compound of said metallic base,

material which includes said base while said element contains said carbon 1n solutlon,

' whereby to form said cyanogen compound.

21. The process of fixing nitrogen which includes preparing a mass comprising carbon intimately associated with an element of the iron group in the solid phase whichis capable f dissolving carbon and of thereby.

rendering said carbon reactive to combine wlth free nitrogen and a metalllc base to form a cyanogen compound of said metallic base, and subjecting said mass to the action of an electric current and to free nitrogen and material which includes said base ,while said element contains said carbon in solution whereby to form said cyanogen compound.

22. The process of fixing nitrogen which includes preparing a mass comprising :car-

bon intimately associated with a finely divided element of theiron group which is .capable'of dissolving carbon and of thereby rendering said'carbon reactive to combine with free nitrogen and a metallic base to form a cyanogen compound of said metallic base, and subjecting said mass to the action of an electric current and to free nitrogen and material which includes said base while said element contains said carbon in solution whereby to form said cyanogen compound.

23. The process of fixingnitrogen which 7 includes preparing a porous briqueted mass comprising carbon intimately associated with an element of the iron-groupin the solid phase which is capable of.dissolving carbon and of thereby rendering said carbon reactive to combine with free nitrogen and a metallic base to form a cyanogen.

compound of said. metallic base, and subjecting said mass to the action of an electric current and to free. nitrogen and material which includes said base while said element solving carbon and' of thereby rendering said carbon'reactive to combine with free nitrogen and a metallic base to form a cyanogen compound ofsai'dmetallic base,

trogen which includes said base while said element conv tains said carbon in solution, whereby to form said cyanogen compound.

25. The process of fixing nitrogen which includes preparinga porous briqueted mass comprising carbon intimately associated with an element of the iron group in the solid phase, which is capable of dissolving carbon. and of thereby rendering said carbon reactive to combine with free nitrogen and a metallic base to form a cyanogen compound of said metallic base, subjecting said mass to the action of an electric current and to free nitrogen and material which includes said base while said element contains said carbon in solution whereby to form said cyanogen compound, and extending the length of the columnar mass during the operation as the decreasing resistivity of said mass, due to the heating thereof, permits.

26. The process of making cyanid which comprises subjecting a resistor in an electric furnace to the action of an electric cur- .from a source extraneous to said resistor.

27. The process of making cyanid which comprises subjecting a resistor in an electric furnace to the action of an electric current of high density whereby to substantially uniformly heat said resistor to a temperature suflicient to cause at least one of the ingredients of the resistor itself to actively and another to catalytically participate in a cyanid forming reaction while supplying an additional participant for said reaction in gaseous form from a source extraneous to said resistor.

28. The process of making cyanid which comprises subjecting a resistor in an electric furnace to the action of an electric current of high density whereby to heat said at least one of the ingredients of the resistor itself to catalytically participate in tric furnace to the action of an electric current of high density whereby to heat said resistor to a temperature sulficient to cause at least one of the'ingredients of the resistor .itself to actively participate, and a second and, carbon dissolving ingredient to catalytiresistor to a temperature suificient to cause forming reaction which in part at least- 'regulates the temperature conditions in said mass by removing heat from portions thereof at which the reaction is proceeding with excessive violence, and further making provision for' temperature regulation by providing in said mass as one of the aforesaid constituents a'material which is subject to a change in phase as the predetermined temperature limit is approximated.

31. In means for fixing atmospheric nitrogen, an electric furnace havinga catalytic resistor, constituents ofwhich are capable of participating in a cyanogen compound forming reaction, said .resistor being substantially free from supports or binders for said constituents which are forei to said reaction, and means for passing ree nitrogen into contact with said resistor to promote said reaction. 7 v

32. Inimeans for fixing atmospheric initrogen, an electric furnace having a catalytic resistor, constituents of which are capable of participating; in a cyanogen-compound forming reaction, saidresistor being substantially free from substances which would impede said reaction, and means for passing free-nitrogen into contact with said resistor to promote said reaction. v 33. In means for fixing atmospheric nitrogen, an electric heating apparatus having a resistor, constituents of which are capable of participating in a cyanogen compound forming reaction, one of said constituents being a catalyzer for said reaction, and means for passing free nitrogen into contact with said resistor,

. 34. In means for fixing atmospheric nitrogen, an electric heating apparatus havin a resistor, constituents of which arecapa le of participating in a cyanogen com-- pound forming reaction, one of said 'constituents-hem a catalyzer and another being substantla yash-free carbon, and means for passing free nitrogen into contact withv said resistor. I

35. In means for fixing atmosphericnitrogen, an electric heating apparatus having. an intersticed resistor, constituents. of -which are capable of participating in a cyanogen compound forming reaction, one

of said constituents being a catalyzer and another bein substantially ash-free carbon,

" and means or passing free nitrogen into contact with said resistor.

36. In means for fixing atmospheric ni-' -trogen, an electric heating apparatus havresistor, constituents of w of participating in a cyanogen compound .ing an intersticed resistor, constituents of which are capable of participating in a. cyanogen compound forming reaction, one of saidconstituents bein a catalyzer and another being substantial y ash-free carbon deposited in the interstices of said resistor from carbon monoxid, in part at least through the intermediacy. of said catalyzer, and means for passing free'nitrogen into contact with said resistor. .c

37. 11 means for fixing atmospheric nitrogen, an electric heating apparatus having an mtersticed resistor, constituents of which are capable of participating in a cyanogen compound forming reaction, one of said constituents being a catalyzer for said reaction, means to pass nitrogen through the in- 'terstices of said resistor and means to establish a reaction zone in said resistor, said apparatus having provisions for eifecting a relative movement between said zone establishing means and said resistor. 38. In means for fixing atmospheric nitrogen, an electric heating apparatus having a resistor, constituents of which are capable of participating in a cyanog 11 compound forming. reaction, one of said constituents being a catalyzer for said reaction, means to supply nitrogen to said resistor, means to establish a reaction zone in a part only of said resistor, and means to dispose said zone successively in difierentparts of said resistor. I g

39. In means for fixingflatmospheric nitro gen, an electric heating apparatus having a resistor, constituents of which are capable of participating ina cyanogen compound forming reaction, one of said constituents being a catalyzer for said reaction, means to supply nitrogen to said resistor, means to establish a reaction zone in a part .only of said resistor, and means to dispose said zone successively in different .parts of said resistor by the action ofgravity upon said resistor;

40. In means for fixing atmospheric nitrogen, an electric heating apparatus having a resistor, constituents of-which are capable of participating in a cyanogen compound forming reaction to be effected within said resistor, one of said constituents being volatilizable duringthe course of said reaction, and another being a solid catalyzer for said reaction, said apparatushaving provisions to co-act with its resistor to prevent such an 7 accumulation of said volatiliz'able constituent in the liquid phase thereof, as would flood the surface of said catalyzer in parts of said, resistor and thereby impede said reaction. l I

41. In means for fixing atmospheric nitrogen, an electric heating appiiratus havin a 'ch are capa lo forming reaction to be effected within said resistor, said resistor having conduits time 130.

through for the passage of gaseous matters and having the interior surfaces thereof which are in communication with said on duits, greatly extended to favor said reac tion and the volatilization of the product formed, and means co-acting with said resistor to electrically heat the latter to cause said reaction and to volatilize said product.

42. The process of fixing nitrogen which comprises incorporating ash-free carbon in.

a catalytic mass in part at least through the action of the catalyzer in said mass 'upon carbon-monoxid, and treating said mass with nitrogen'and as a resistor in an electric furnace to combine said nitrogen with said carbon.

4:3. The process of fixing nitrogen which comprises incorporating ash-free carbon, in r a catalytic mass in part at least through the action of'the catalyzer in said mass upon carbon-monoxid while at the same time preheating said mass through the conversion of the carbon-monoxid to carbon dioxid, and treating said mass with nitrogenand as a resistor in an electric furnace toocombine said nitrogen with said carbon.

44. The method of operating an electric furnace for the production of a cyanogen compound, which includes supplying free nitrogen to a reaction zone inv a resistor in said furnace, which resistor comprises a catalytic mass in which are present carbon,

a solvent for said carbon and a substance which is capable .of being volatilized by the .heat generated in said resistor and when thus volatilized of supplying the base of the cyanogen compound to be formed in said reaction zone, and effecting a relative movement between said resistor and parts of said furnace whereby to subject escaped volatilized portions of said substance to said reaction in saidzone. v

45. The method of operating an electric furnace for the production of'a cyanogen compound, which includes supplying free nitrogen to a cyanogen compound forming reaction zone in a resistor in said furnace,

which resistor comprises a moving mass in which are present carbon, a catalyzer capable of promoting a cyanogen compound formingreaction, and a substance which is capable ofbeing volatilized by the heat gen.- erated in said reaction zone, the movement Y of said mass being made such as to return to said zone escaped-portions of said substance. Y

.46. The method of operating .an electric furnace for theproduction of a'cyanoge compound which includes using as a resisto in said furnace a mass of material constituents of which participatev in the cyanogen compound forming reaction, one of said con- Y 'stituents participating catalytically and cffectin g acirculation of one of said constituents through said mass, in part at least by temperature of said carbon-monoxid to convert the same to carbon-dioxid.

48. The method of operating electric heating apparatus to effect the formation of'a cyanogen compound in a reaction zone in said apparatus, which comprises using as a resistor in said apparatus a mass which includes a oatalyzer for said reaction, which catalyzer is also capable of converting carbon-monoxid to carbon-diox'id at temperatures below that at which said cyanogen compound is formed, supplying a mixture of'nitrogen and carbon-monoxid directly to said reaction zone, combining said nitrogen with constituents of said resistor to form said cyanogen compound, and subsequently converting said carbon-monoxid to carbondioxid while depositing carbon, through the intermediacy of said catalyzer.

49. The method of operating an electric furnace which comprises treating a catalytic resistor for said furnace, to be used in the production of a cyanogen compound, wlth carbon monoxid to deposit carbon thereupon, and subjecting said resistor to the action of nitrogen to combine said carbon and nitrogen.

50. The method of operating an electric furnace which comprises treating a catalytic resistor for said furnace with carbon monoXid to deposit carbon thereupon and to aid in preheating said resistor, elevating the temperature of said resistor'to a temperature sufficient to effect a cyanogen forming reaction-in which said carbon participates, and

subjecting said resistor to the action of nitrogen to combine said carbon and nitrogen.

51. Themethod of producing a cyanogen compound which comprises treating a porous catalytic resistor one at least of the constituents of which participates in a reaction to form said cyanogen compound with gase ous material to supplythe remaining con stituent or constituents for said' compound, and removing said compound, when formed, from a part at least of said resistor in the gaseous phase.

52. The process of fixing nitrogen which comprises preheating a catalytic resistor the parts of which are movable with respect to each other and which parts are relatively poor conductors of heat, and said parts to efiect a relatively uniform distribution of said heat through the mass,'and subjecting said resistor to the action of an elective current and free nitrogen to combine '5 said nitrogen with at least one constituent of said resistor. v

In testimony whereof I have afiixed my signature, in the presence of two witnesses.

. JOHN E. BUCHER.

\ Witnesses: r i

NORMAN E. HoL'r,

v THOMAS H. Roimn'rs, 

